Troy Aikman started the first game of his rookie season. Five years later, his coach — Jimmy Johnson — was a two-time Super Bowl champion.

Likewise, fellow first-round pick Kyle Boller started the first game of his rookie season. But five years after he did, his coach — Brian Billick — was out of a job.

Same starting point. Two vastly different destinations.

So what should the Dolphins do with Ryan Tannehill — their hot-shot first-round pick who might start Friday night’s preseason game against the Carolina Panthers (8 p.m., CBS 4)?

Johnson succeeded in Dallas with the baptism-by-fire approach, but surprisingly suggestions caution. Billick is in the Fox broadcast booth largely because Boller didn’t pan out, yet thinks the Dolphins should name Tannehill as their guy, as soon as possible.

“If you’re going to draft a guy in the first round, you’re going to play him,” Billick said this week. “It’s the only to learn. That’s what the league demands right now.

“That organization will be better, Day 1 at the start of 2013 season, for every snap that Ryan Tannehill plays this year.”

Johnson sees it differently.

The former Cowboys, Dolphins and University of Miami coach said last week that Tannehill should only start ahead of Matt Moore (and David Garrard, whenever he returns from injury) if he gives Miami the best chance to win now.

“You don’t want to kill anybody’s confidence if he’s not ready to play,” Johnson added. “We could survive it in Dallas because we were a bad team and we were going to lose anyway. I could have a loss with a guy who couldn’t play, or a guy who could play.”

As for the only opinion that matters — that of Dolphins coach Joe Philbin — his view, at least expressed publicly, mirrors Johnson’s philosophy. It might just be the case that Philbin decides Tannehill is the quarterback that gives Miami its best shot to compete.

Tannehill, the eighth overall pick in last April’s draft, was solid in his preseason debut, completing 14 of 21 passes for 167 yards and a touchdown, albeit against Tampa Bay’s backups. He carried that over into an even better week of practice, showing a greater command of Mike Sherman’s hurry-up offense than Moore.

“I dang sure hope so,” Tannehill said this week, when asked if he’s improved since training camp began. “It’s a waste of time if I haven’t improved. I feel like I’ve gotten better every day.”

Philbin has yet to name a starter for the team’s first road test Friday, but did say Tannehill will get work with the first-team offense at some point in the preseason.

He had hoped to have an opening-day quarterback picked by next week, but seemed to back off that soft deadline over the past few days.

For sure, the knee injury to Garrard — suffered not on the football field, but while in his backyard — has forced the Dolphins to improvise. But here’s another thought: Maybe Miami is going to give Tannehill every possibility to win the job by Sept. 9, when the Dolphins open in Houston.

“I like his demeanor, I like his poise, I like his approach to the game,” Philbin said of Tannehill this week. “I think he’s a serious person. I think he would be a guy that, at least as a coach, you could go to bed on Saturday night and say that the guy is going to do whatever he can to prepare himself well.”

And here’s the dirty little secret about first-round picks, at least at the quarterback position: They’re a crapshoot, whether you baby them or not.

Of the 41 quarterbacks taken in the first round from when Aikman went first overall in 1989 through 2007, just 16 remained with their original team for more than five seasons (a reasonable benchmark for success).

By this metric, rookies who started right away have had a success rate of 44 percent, while those who are brought along more gradually have panned out just 38 percent of the time.

Cam Newton, Carolina’s versatile triggerman, proved last year that there’s no time like the present for young quarterbacks. Newton started every game of his first professional season and broke eight NFL records, including most total touchdowns by a rookie. (He had 35.)

Newton, who is expected to play the first half of Friday’s affair in Charlotte, joined the Bengals’ Andy Dalton as the first pair of rookie quarterbacks to make the Pro Bowl.

That’s why Billick is advocate of the sink-or-swim approach, and believes that, by holding a training camp competition, the Dolphins are robbing Tannehill of vital practice experience that he needs to succeed.

“There’s nothing not to like about him,” Billick said. “I think he could be an excellent quarterback.”

The Dolphins agree. But is he ready to be a starting quarterback? The answer could come into focus Friday night.